Computational models can be used to simulate a prototype of electrohydrodynamic (EHD)ion-drag micropump with planar emitter and micropillar collector electrodes.In this study,a simple and inexpensive design of an ion-drag micropump was modeled and numerically simulated.A three-dimensional segment of the microchannel was simulated by using periodic boundary conditions at the inlet and outlet.The pressure and velocity distribution at the outlet and in the entire domain of the micropump was obtained numerically.The effect of the gap between the emitter and the collector electrode,width and the height of micropillar and flow channel height was analyzed for optimum pressure and output flow rate.